AR8K Sputtering Squelch Fix

I tried the hardware squelch jitter cure recently posted to the ar8000 mail list and can confirm it does make a dramatic improvement, enough so that I'm actually using my AR8K again instead of just letting it sit on the shelf.

For those asking how to find out where C96 is, here are three photos, each successively moving in closer to help you find the location.

While the mod says to replace the original .01 uF capacitor C96 with a 2.2uF or 4.7uF part, I found it easier to simply parallel it across the existing surface mount part. There's plenty of room inside for the typically small round electrolytic capacitor if you lay it on its side. Also, rather than directly soldering the new cap in, I soldered in a couple of round IC socket pins. This allowed me to easily plug and unplug various values for testing. I ended up using a 3.3uF capacitor. Note, the negative end of the capacitor connects to the upper pin in these photographs.

I haven't bothered giving directions for opening up the AR8K case, that's already well covered in other places. The first photo here identifies the IF board as the one with the controls attached near the top. The second photo shows a closer look where the capacitor is bridged across C96 and plugged into the two IC socket pins. The final photo shows a closer look exactly where C96 is.

jpg jpg
jpg

Many thanks to Andrew McKernan (mckernan@dircon.co.uk) for originally posting the fix to the ar8000 mail list.

Greg Saville (gregsa@teleport.com)